As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
STRONG UNPLEASANT ODOR FROM AIR CONDITIONING SOON AS PACKS TURNED ON. USING BLEED AIR FROM APU A/C AIR HAS LIGHT ODOR. FOUND OIL ODOR IN APU BLEED AIR DUCT DOWNSTREAM OF BLEED AIR VALVE. REPLACED APU REF 49 11 00 400 803 STEP L PG 10. COMPLETED INSTALL OF APU IAW 49 0 400 803. OPS AND LEAK CHECK GOOD IAW 49 11 0 400 803.